Mercedes is expected to add a four-door SUV to its line-up to rival cars such as BMW's X6 4x4 coupe.
The company has revealed that an all-new model will be built at its US base in Alabama, and that it has invested $350m (around £220m) in the factory to prepare for production.
No official announcement has been made, but Mercedes sources have hinted that a new SUV is on the way.
This is despite figures showing that BMW's X6 has recorded sales of just 6087 cars since it was launched in September 2008.
A Mercedes spokesman confirmed that any new model would not be released before 2013 at the earliest.
Further information is expected at the Detroit motor show in January.